Kakuro
A crossword made of numbers: every run adds up.
About Kakuro
Kakuro, also called cross sums, is a number crossword loved by Sudoku players. Clues give the sum of each run, and knowing which digit sets make each sum is the key. Every puzzle here has exactly one solution.
How to play
Fill the white cells with digits 1–9. Each run of white cells, across or down, must add up to the clue in the black cell before it (across sums above the diagonal, down sums below), and no digit may repeat within a run.
Tips and strategies
- Some sums have only one digit set: 3 in two cells is 1+2, 4 is 1+3, 16 is 7+9, 17 is 8+9.
- Where an across and a down run cross, the digit must fit both runs' possible sets.
- Use notes for candidates, and remember digits never repeat within a run.
Kakuro strategy guide
Learn the unique sums. A two-cell run of 3 is always 1+2, 4 is 1+3, 16 is 7+9 and 17 is 8+9; a three-cell 6 is 1+2+3 and 24 is 7+8+9. These runs allow only one set of digits, so start there.
Where an across run and a down run cross, the cell must fit both. If one run allows only {1, 2} and the other only {2, 4}, the crossing cell is 2.
Subtract what you know. Once all but one cell of a run is filled, the last digit is the clue minus the others — and it must still be 1–9 and not repeat in its run.
Frequently asked questions
How do I play Kakuro?
Fill the white cells with digits 1–9. Each run of white cells across or down must add up to the clue in the black cell before it, and no digit may repeat within a run.
What are the board sizes?
6×6, 8×8 and 10×10, counting the black clue row and column along the top and left. Bigger boards have longer runs and more crossings.
Does every Kakuro have one solution?
Yes. A solver checks every puzzle and only unique ones are offered. No digits are given; the sums are the only clues.
Is Kakuro free to play?
Yes. Every game on Puzzimo is completely free and runs in your browser on desktop, tablet and phone — no download or installation.
Do I need an account?
No. You can play instantly as a guest and still appear on the leaderboards. Sign in with Google, Discord or LINE to keep your scores on every device.
How does the daily Kakuro challenge work?
Every day at 00:00 UTC everyone gets the same new puzzle. Only your first finish of the day counts on the leaderboard.
How are leaderboard results verified?
Our servers replay every move of your game and measure the time themselves, so leaderboard results can't be faked.